Problem: There are N men and N women, both numbered 1, 2, \ldots, N.

For each i, j (1 \leq i, j \leq N), the compatibility of Man i and Woman j is given as an integer a_{i, j}. If a_{i, j} = 1, Man i and Woman j are compatible; if a_{i, j} = 0, they are not.

Taro is trying to make N pairs, each consisting of a man and a woman who are compatible. Here, each man and each woman must belong to exactly one pair.

Find the number of ways in which Taro can make N pairs, modulo 10^9 + 7.

Constraints

* All values in input are integers.
* 1 \leq N \leq 21
* a_{i, j} is 0 or 1.

Input

Input is given from Standard Input in the following format:


N
a_{1, 1} \ldots a_{1, N}
:
a_{N, 1} \ldots a_{N, N}


Output

Print the number of ways in which Taro can make N pairs, modulo 10^9 + 7.

Examples

Input

3
0 1 1
1 0 1
1 1 1


Output

3


Input

4
0 1 0 0
0 0 0 1
1 0 0 0
0 0 1 0


Output

1


Input

1
0


Output

0


Input

21
0 0 0 0 0 0 0 1 1 0 1 1 1 1 0 0 0 1 0 0 1
1 1 1 0 0 1 0 0 0 1 0 0 0 0 1 1 1 0 1 1 0
0 0 1 1 1 1 0 1 1 0 0 1 0 0 1 1 0 0 0 1 1
0 1 1 0 1 1 0 1 0 1 0 0 1 0 0 0 0 0 1 1 0
1 1 0 0 1 0 1 0 0 1 1 1 1 0 0 0 0 0 0 0 0
0 1 1 0 1 1 1 0 1 1 1 0 0 0 1 1 1 1 0 0 1
0 1 0 0 0 1 0 1 0 0 0 1 1 1 0 0 1 1 0 1 0
0 0 0 0 1 1 0 0 1 1 0 0 0 0 0 1 1 1 1 1 1
0 0 1 0 0 1 0 0 1 0 1 1 0 0 1 0 1 0 1 1 1
0 0 0 0 1 1 0 0 1 1 1 0 0 0 0 1 1 0 0 0 1
0 1 1 0 1 1 0 0 1 1 0 0 0 1 1 1 1 0 1 1 0
0 0 1 0 0 1 1 1 1 0 1 1 0 1 1 1 0 0 0 0 1
0 1 1 0 0 1 1 1 1 0 0 0 1 0 1 1 0 1 0 1 1
1 1 1 1 1 0 0 0 0 1 0 0 1 1 0 1 1 1 0 0 1
0 0 0 1 1 0 1 1 1 1 0 0 0 0 0 0 1 1 1 1 1
1 0 1 1 0 1 0 1 0 0 1 0 0 1 1 0 1 0 1 1 0
0 0 1 1 0 0 1 1 0 0 1 1 0 0 1 1 1 1 0 0 1
0 0 0 1 0 0 1 1 0 1 0 1 0 1 1 0 0 1 1 0 1
0 0 0 0 1 1 1 0 1 0 1 1 1 0 1 1 0 0 1 1 0
1 1 0 1 1 0 0 1 1 0 1 1 0 1 1 1 1 1 0 1 0
1 0 0 1 1 0 1 1 1 1 1 0 1 0 1 1 0 0 0 0 0


Output

102515160

Solution (in JAVA):

Solution:
import java.awt.*;
import java.io.*;

import java.math.BigInteger;
import java.util.*;

public class Main {

    static int n, mod = (int)1e9 + 7;
    static long OO = (long)1e15;
    static Long memo[][];
    static int[][]arr;

    static long solve(int idx , int mask)
    {
        if(idx == n)
            return (1<<n) - 1 == mask?1:0;
        if(memo[idx][mask] != null) return memo[idx][mask];

        long ans = 0;
        for (int j = 0; j < n ;j++ )
            if(arr[idx][j] == 1 && ((1<<j)&mask) == 0)
                ans = (ans + solve(idx + 1, mask|(1<<j)))%mod;

        return memo[idx][mask] = ans;
    }

    public static void main(String[] args) throws Exception {

        Scanner sc = new Scanner(System.in);
        PrintWriter pw = new PrintWriter(System.out);

        n = sc.nextInt();
        arr = new int[n][n];

        for (int i = 0 ; i < n ; i++)
            for (int j = 0 ;j < n ; j++)
                arr[i][j] = sc.nextInt();

        memo = new Long[n][1<<n];
        pw.print(solve(0 , 0));


        pw.close();
    }
    static class Point implements Comparable<Point>
    {
        int x ,y ;

        public Point(int x, int y) {
            this.x = x;
            this.y = y;
        }

        @Override
        public int compareTo(Point o) {
            if (x == o.x) {
                return y - o.y;
            }
            return x - o.x;
        }

        @Override
        public String toString() {
            return "Point{" +
                    "x=" + x +
                    ", y=" + y +
                    '}';
        }
    }

    static class Circle implements Comparable<Circle>
    {
        int x , radius ,idx;
        public Circle(int x , int r , int idx)
        {
            this.x = x;
            this.radius = r;
            this.idx = idx;
        }

        public boolean isInside(Point p)
        {
            return (p.x - x)*(p.x - x) + (p.y)*(p.y) <= radius * radius;
        }

        @Override
        public String toString() {
            return "Circle{" +
                    "x=" + x +
                    ", radius=" + radius +
                    '}';
        }

        @Override
        public int compareTo(Circle o) {
            return x - o.x;
        }
    }

    private static long gcd(long a, long b) {
        if( b == 0)
            return a;
        return gcd(b  , a%b);
    }

    static long lcm(int a, int b)
    {
        return (a*b)/gcd(a, b);
    }


    private  static int dis(int xa , int ya , int xb , int yb)
    {
        return (xa-xb)*(xa - xb) + (ya- yb)*(ya-yb);
    }


    static class Pair implements Comparable<Pair> {
        int x,y;


        public Pair(int x, int y) {
            this.x = x;
            this.y = y;
        }

        public int compareTo(Pair o) {
            if (y  == o.y)
                return x - o.x;
            return y - o.y;

        }

        public double dis(Pair a){

            return (a.x - x)*(a.x - x) + (a.y-y)*(a.y-y);
        }

        public String toString() {
            return  x+" "+ y;
        }
        public boolean overlap(Pair a)
        {
            if((this.x >= a.x && this.x <= a.y) || (a.x >= this.x && a.x <= this.y)) return true;
            return false;

        }
    }

    static class Scanner {
        StringTokenizer st;
        BufferedReader br;

        public Scanner(FileReader r) {
            br = new BufferedReader(r);
        }

        public Scanner(InputStream s) {
            br = new BufferedReader(new InputStreamReader(s));
        }

        public String next() {
            while (st == null || !st.hasMoreTokens()) {
                try {
                    st = new StringTokenizer(br.readLine());
                } catch (IOException e) {
                    throw new RuntimeException(e);
                }
            }
            return st.nextToken();
        }

        public boolean check() {
            if (!st.hasMoreTokens())
                return false;
            return true;
        }

        public int nextInt() {
            return Integer.parseInt(next());
        }

        public long nextLong() {
            return Long.parseLong(next());
        }

        public String nextLine() {
            try {
                return br.readLine();
            } catch (Exception e) {
                throw new RuntimeException(e);
            }
        }

        public double nextDouble() {
            String x = next();
            StringBuilder sb = new StringBuilder("0");
            double res = 0, f = 1;
            boolean dec = false, neg = false;
            int start = 0;
            if (x.charAt(0) == '-') {
                neg = true;
                start++;
            }
            for (int i = start; i < x.length(); i++)
                if (x.charAt(i) == '.') {
                    res = Long.parseLong(sb.toString());
                    sb = new StringBuilder("0");
                    dec = true;
                } else {
                    sb.append(x.charAt(i));
                    if (dec)
                        f *= 10;
                }
            res += Long.parseLong(sb.toString()) / f;
            return res * (neg ? -1 : 1);
        }

        public boolean ready() {
            try {
                return br.ready();
            } catch (IOException e) {
                throw new RuntimeException(e);
            }
        }
    }
}